Abstrakty - geoinformatica

GEOINfORMATICA POLONICA
11: 2012
SpiS treści
Artykuły
Tadeusz CHROBAK
Mapa a geoinformatyka . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Adam LINSENBARTH
Etapy rozwoju geoinformacji o terenach biblijnych – od iii tysiąclecia przed Chr. do czasów współczesnych . . . . . . . . 17
Ewa KRZYWICKA-BLUM
Funkcje użytkowe współczesnych map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Dariusz GOTLIB
Mapy mobilne – modelowanie prezentacji kartograficznej . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Zbigniew SZCZERBOWSKI
Geologiczne i górnicze uwarunkowania zaburzeń przebiegu geoidy na przykładzie rejonu Inowrocławia . . . . . . . . . . . 49
Robert OLSZEWSKI
Rola i miejsce kartografii w kształtowaniu infrastruktury informacji przestrzennej . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Zbigniew KASINA
Analiza efektywności jednoczesnej inwersji pierwszych wstąpień fali refragowanej i czołowej – studium modelowe . . 67
contentS
Papers
Tadeusz CHROBAK
The map and geoinformatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Adam LINSENBARTH
Stages of geoinformation evolution related to the territories described in the Bible – from the 3rd millennium
b.C. to modern times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Ewa KRZYWICKA-BLUM
Usable functions of modern maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Dariusz GOTLIB
Mobile maps – modelling of cartographic presentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Zbigniew SZCZERBOWSKI
Geological and mining conditions of disturbances in the geoid course on the example of the region of Inowrocław . . .49
Robert OLSZEWSKI
The role and place of cartography in the development of the spatial information infrastructure . . . . . . . . . . . . . . . . . . .57
ZBIGNIEW KASINA
The analysis of the effectiveness of simultaneous inversion of turning and head waves first breaks - model study . . . . .67
GEOINfORMATICA POLONICA
11: 2012
TADEUSZ CHROBAK1
tHe MAp AnD GeoinForMAticS
Key words:
cartography, geoinformatics, computer science, geostatistics
Abstract
The article presents the relationship between cartography and geoinformatics affecting their scientific and socioeconomic development.
MAPA A GEOINfORMATYKA
Słowa kluczowe:
kartografia, geoinformatyka, informatyka, geostatystyka
Abstrakt
W artykule przedstawiono wzajemne relacje kartografii i geoinformatyki mające wpływ na ich rozwój naukowy
i społeczno-gospodarczy.
1. introduction
In August 1995 in Barcelona, the General Assembly of the International Cartographic Association (ICA)
approved the definition of cartography as a science dealing with the conception, production, dissemination and
study of maps.
The development of automation, information
technology and telecommunication is the beginning of
the new technology at work on the acquisition, processing and visualization. Its beginning dates back to 1963,
1
when the first cadastral system, a computerized system in
which maps constituted an integral part, was developed in
Canada. The concept of geoinformatics as a science (GI
- Science) was first introduced by Goodchild in 1992.
Cartography was formed in three historical periods:
from the ancient times to the Renaissance, from the midsixteenth to the mid-twentieth century, and since the midtwentieth century. The map, however, from its inception
was the system, despite its analogue form. Changing technologies in cartography to digital resulted in the fact that
digital maps are understood as specific models of space
The paper is a part of the Research Project NN 526 064 340
Chair of Geomatics, AGH – University of Science and Technology, Krakow
GEOINfORMATICA POLONICA
11: 2012
ADAM LINSENBARTH1
StAGeS oF GeoinForMAtion eVoLUtion reLAteD to tHe territorieS
DeScriBeD in tHe BiBLe – FroM tHe 3rD MiLLenniUM B.c. to MoDern tiMeS
Key words:
Bible, geoinformation, geography, cartography, history
Abstract
The paper presents consecutive stages of the evolution of geoinformation related to the territories of the events
described in the Bible. Two geoinformation sources are presented: the Bible and non-Bible sources. In the Bible there is
much, often some highly detailed information regarding terrain topography. The oldest non-Bible sources are incorporated
in the ancient documents, which were discovered in Egypt and Mesopotamia. Some of them are related to the 3rd millennium B.C. The further stages are related to the onomasticons and itineraries written by travellers and pilgrims to the Holy
Land. The most famous onomasticons include: onomasticons prepared by bishop Eusebius from Caesarea and those prepared by St. Jerome. One of the oldest maps of Palestine’s territory is the so-called mosaic map of Madaba dated to 565. In
the 15th century several Bible maps were edited. The most rapid evolution occurred in the 16th and 17th centuries, when the
world famous cartographers such as Mercator and Ortelius edited several maps of Palestine’s territory. Cartographers from
several European countries edited more than 6,000 maps presenting the Biblical territories and Biblical events. Modern
maps, based on detailed topographical surveys, were edited in the second half of the 19th and 20th centuries.
ETAPY ROZWOJU GEOINfORMACJI O TERENACH BIBLIJNYCH –
OD III TYSIĄCLECIA PRZED CHR. DO CZASÓW WSPÓŁCZESNYCH
Słowa kluczowe:
Biblia, geoinformacja, geografia, kartografia, historia
Abstrakt
W artykule przedstawiono kolejne etapy rozwoju geoinformacji dotyczącej terenów biblijnych. Omówiono dwa
źródła informacji, a mianowicie geoinformacje biblijne i pozabiblijne. W tekstach biblijnych można znaleźć wiele, często
bardzo detalicznych informacji topograficznych. Najstarsze źródła pozabiblijne, to starożytne dokumenty odnalezione na
1
Institute of Geodesy and Cartography
18
ADAM LINSENBARTH
terenach Egiptu i Mezopotamii. Niektóre z nich pochodzą z trzeciego milenium przed Chr. Kolejnym etapem geoinformacji
były onomastikony oraz dzienniki podróży pisane przez podróżników i pielgrzymów do Ziemi Świętej. Do najbardziej
znanych należy onomastikon sporządzony przez biskupa Euzebiusza z Cezarei oraz onomastikon św. Hieronima. Do jednych z najstarszych map Palestyny należy mozaikowa mapa odnaleziona na posadzce kościoła w Madabie pochodząca
z roku 565. Szybki rozwój kartografii biblijnej nastąpił w wieku XVI i XVI, kiedy to słynni kartografowie Mercator
i Ortelius opracowali wiele map Palestyny. Kartografowie z wielu krajów Europy, w ciągu minionych stuleci, opracowali
ponad 6 tysięcy map biblijnych przedstawiających terytoria i wydarzenia biblijne. Nowoczesne mapy, oparte na pomiarach
topograficznych, zaczęto wydawać w drugiej połowie XIX wieku oraz w wieku XX.
1. introduction
The area described in the Bible covers all those
places where events presented in the Old Testament and
in the New Testament occurred. It is, therefore, a vast area
stretching from the east to the west of ancient Mesopotamia to Italia, and from the north to the south between
the area of modern Turkey and Egypt (Rainey, 2002). The
events described in the Old Testament took place within
the areas called the fertile Crescent, whose north-eastern
arm was made up by Mesopotamia, lying in the bifurcation of the Euphrates and Tigris Rivers, and its south
arm was made up by the territories of modern Israel and
Egypt. The central part of the fertile Crescent is the area
of ancient Palestine, where most of the events presented
in the Old Testament and in the New Testament occurred
(Linsenbarth, 2007). The events described in the New
Testament, related mostly to missionary journeys of St.
Paul the Apostle, and covered additionally the territories
of modern Turkey, Greece and Italy.
The areas covered by Biblical events constitute an
ideal example illustrating the development of broadly understood spatial information systems (Linsenbarth, 2008b,
Linsenbarth 2010a). It results from both geopolitical and
geographic locations of this area, but also from the fact
that for many years geographers, historians and cartographers have focused their attention on this exceptional part
of our world. It should be noted that although the concept
of geoinformation in its literal meaning was unknown in
the antiquity, yet the first pieces of information describing
geographical space were recorded employing techniques
known in those times.
3. the oldest sources of non-Biblicale information
Undoubtedly, maps drawn in ancient Mesopotamia should be counted among the oldest geoinformation
sources. They were maps carved in clay, similarly to the
majority of Mesopotamian documents. The map drawing
was executed on clay tablets with a sharp triangle-end stylus. In Nuzi, located in north-eastern Iraq, a map carved
towards the end of the 3rd millennium B.C. was excavated.
The map shows an estate belonging to Arzala (Metger,
1997). One of two other maps found in Nippur, in the
south of Iraq, shows a drawing of the town itself as well
as of nearby canals; the other one presents the boundaries
of twelve estates and the names of their owners. These
maps may be well considered to be the first cadastral
maps. Probably, similar maps existed in other areas of the
Middle East.
Many oldest sources of geoinformation are those
written down in various kinds of documents that were
found in the territories of Egypt (Aharoni et al., 2002).
Inscriptions related to the Palestinian territories found on
the tombs at Abydos belong to the oldest ones. They give
a description of five war expeditions during the reign of
Pharaoh Pepi I (2390-2361 B.C.) to the land called “The
Land of Sand-Dwellers” (Aharoni et al., 2002). This name
was used to refer to the area east of Egypt. In these inscriptions, among other things, campaigns in the coastal belt
in the area of Acre in the Jezreel Valley were described.
Also, the promontory of (Karmel) Carmel is quite adequately compared to a nose of an antelope. Much information related to the description of Palestine was given in
the so-called Execration Texts from the 19th century B.C.,
written on clay figurines found in Saqqara in Egypt. In the
GEOINfORMATICA POLONICA
11: 2012
EWA KRZYWICKA-BLUM1
USABLe FUnctionS oF MoDern MApS
Key words:
map functions, computer maps
Abstract
Modern maps created with the application of GIS technology using special techniques and programmes adequate for
spatial information systems are, in comparison to their analogue counterparts, of better model qualities, which is obtained
by separating their practical functions. The cognitive function of maps is the main priority. The shape of a map is a result
of the applied technology, yet the maps developed using many technical instruments are not always the best ones or graphically correct. There have been many beautiful maps of landscape attempting to show different aspects of landscapes and
the results of analyses of multifactorial phenomena and processes.
fUNKCJE UŻYTKOWE WSPÓŁCZESNYCH MAP
Słowa kluczowe:
funkcje map, mapy komputerowe
Abstrakt
Mapy tworzone w warunkach nowoczesnej techniki komputerowej, technologii i organizacji właściwej systemom
informacji przestrzennej, cechuje podwyższenie, w stosunku do analogowych, własności modelowych uzyskuje się to
dzięki rozdzieleniu funkcji praktycznych. Walory poznawcze mapy stanowią, w całym rozwoju kartografii wartości priorytetowe. Postać mapy jest wynikiem zastosowanej technologii i nie zawsze mapy opracowane w interaktywnym procesie
są graficznie poprawne. Pojawiają się nowe ujęcia treści map krajobrazowych i bardzo piękne propozycje ujęć wyników
analiz wieloczynnikowych zjawisk i procesów.
1
Institute of Geodesy and Geoinformatics, Wrocław University of Environmental and Life Sciences
GEOINfORMATICA POLONICA
11: 2012
DARIUSZ GOTLIB1
MoBiLe MApS – MoDeLLinG oF cArtoGrApHic preSentAtion
Key words:
mobile cartography, mobile maps, mobile GIS, geovisualization, navigation applications, LBS
Abstract
The article focuses on the cartographic design aspects of mobile navigation and location applications. The relationship between the conceptual model of spatial data and the cartographic presentation model is discussed. An example of
a formal description of cartographic presentation that uses the concepts: partial geocomposition, cartographic information
transmission unit, cartographic event, geovisualization window and elementary geovisualization is presented. The paper
shows potential benefits of applying the proposed methodology, primarily the ability to create a description of cartographic
presentation, which is independent of specific technologies used by the applications of different manufacturers.
MAPY MOBILNE – MODELOWANIE PREZENTACJI KARTOGRAfICZNEJ
Słowa kluczowe:
kartografia mobilna, mapy mobilne, mobilny GIS, geowizualizacja, aplikacje nawigacyjne. LBS
Abstrakt
W artykule zwrócono uwagę na kartograficzne aspekty projektowania mobilnych aplikacji nawigacyjnych
i lokalizacyjnych. Pokazano zależności pomiędzy modelem pojęciowym danych przestrzennych a modelem prezentacji kartograficznej. Przedstawiono przykład formalnego opisu prezentacji kartograficznej wykorzystującego pojęcia:
geokompozycja składowa, jednostka przekazu kartograficznego, zdarzenie kartograficzne, okno geowizualizacji, geowizualizacja elementarna. Omówiono potencjalne korzyści wynikające ze stosowania omawianej metodyki, przede wszystkim
możliwość tworzenia opisu (definicji) prezentacji kartograficznych niezależnego od konkretnych technologii poszczególnych producentów aplikacji.
1
Department of Cartography, faculty of Geodesy and Cartography, Warsaw University of Technology
GEOINfORMATICA POLONICA
11: 2012
ZBIGNIEW SZCZERBOWSKI1
GeoLoGicAL AnD MininG conDitionS oF DiStUrBAnceS
in tHe GeoiD coUrSe on tHe eXAMpLe oF tHe reGion oF inoWrocłAW2
Abstract
Problems of modelling of geoid and quasi-geoid course are usually considered in Polish literature in the context of
the expected accuracy, which enables the implementation of satellite techniques for altitude measurements with accuracy
comparable to the geometric levelling. The difficulties that are associated with this modelling are usually referenced to the
mountainous areas, i.e. where given the significant denivelation of the terrain, the course of geoid or quasi-geoid surface is
varied. It appears that the landform features are not the only factors disturbing the course of the above mentioned surface.
This paper shows the difficulties in modelling the quasi-geoid in the area of Inowrocław, where considering the large
changes in the gravitational field, land survey results may give a false picture of its course. The cause for these changes
is geological (deposit of salt domes) and mining (high concentration of voids) conditions. In this case, knowledge of the
geological situation is important in terms of how to implement surveying for precise, centimetre course of geoid or quasigeoid. On the basis of the work of surveying, a quasi-geoid model for the region of Inowrocław was presented.
GEOLOGICZNE I GÓRNICZE UWARUNKOWANIA ZABURZEń PRZEBIEGU GEOIDY
NA PRZYKŁADZIE REJONU INOWROCŁAWIA
Abstrakt
Problematyka modelowania przebiegu geoidy lub quasi-geoidy rozpatrywana jest zwykle w literaturze krajowej
w kontekście oczekiwanych dokładności, które umożliwiłyby realizację pomiarów wysokościowych technikami satelitarnymi o dokładnościach porównywalnych z niwelacją geometryczną. Trudności, jakie związane są z tym modelowaniem
odnoszone są zwykle do obszarów górzystych, tj. takich gdzie z uwagi na znaczną deniwelację terenu przebieg powierzchni geoidy lub quasi-geoidy jest zróżnicowany. Okazuje się, że ukształtowanie terenu nie jest jednym czynnikiem
zaburzającym przebieg ww. powierzchni.
W przedstawionej pracy wskazano na trudności w modelowaniu quasi-geoidy w rejonie Inowrocławia, gdzie z uwagi na duże zmiany w polu siły ciężkości wyniki pomiarów geodezyjnych mogą dawać nieprawdziwy obraz jej przebiegu.
Przyczyną tych zmian są uwarunkowania geologiczne (wysadowe złoże soli) i górnicze (duża koncentracja pustek poeksploatacyjnych). W tym przypadku wiedza o sytuacji geologicznej jest istotna z punktu widzenia sposobu realizacji prac geodezyjnych dla uzyskania precyzyjnego, centymetrowego przebiegu geoidy lub quasi-geoidy. Na podstawie wykonanych
prac geodezyjnych przedstawiony został model quasi-geoidy dla rejonu Inowrocławia.
1
AGH University of Science and Technology. faculty of Mining Surveying and Environmental Engineering, Mickiewicz Avenue 30, 30-059 Krakow, Poland
2
The study was carried out in the framework of AGH-UST research project: 11.11.150.195.
GEOINfORMATICA POLONICA
11: 2012
ROBERT OLSZEWSKI1
tHe roLe AnD pLAce oF cArtoGrApHY in tHe DeVeLopMent
oF tHe SpAtiAL inForMAtion inFrAStrUctUre
Key words:
cartographic modelling, spatial information infrastructure
Abstract
Hundreds of various spatial databases and maps developed using those databases were created in Poland and abroad
in the past decade. The majority of them were created ad hoc, in relation to implementation of current demands of particular
institutions or organisations. Thus, the side effect of rapid development of geoinformation was increasing organisational,
methodological and conceptual chaos. Adoption and successive implementation of resolutions of the EU INSPIRE Directive, as well as the Polish Act on the Spatial Information Infrastructure was the partial solution of the discussed issues.
However, the legal acts of high grade specify only general rules of creation of the geoinformation infrastructure.
The development of modern and functional spatial, reference and thematic databases requires detailed determination of a
conceptual model of particular databases, the ways of their population, utilisation and processing of data stored in those
databases. However, legislative activity is not the most important part of that process; appropriate understanding of surrounding geographic reality, resulting in the development of correct cartographic models, implemented in the form of
spatial databases, is far more important. Therefore, after the period of rapid technological development and fascination of
modern information solutions, the deep methodological reflection is necessary.
ROLA I MIEJSCE KARTOGRAfII W KSZTAŁTOWANIU
INfRASTRUKTURY INfORMACJI PRZESTRZENNEJ
Słowa kluczowe:
modelowanie kartograficzne, infrastruktura informacji przestrzennej
Abstrakt
W minionym dziesięcioleciu powstało, zarówno na świecie, jak i w Polsce, setki różnego rodzaju baz danych
przestrzennych i opracowywanych na ich podstawie map. Większość z nich była tworzona ad hoc w związku z realizacją
bieżących potrzeb danej instytucji czy organizacji. Skutkiem ubocznym gwałtownego rozwoju geoinformacji stał się
zatem narastający chaos organizacyjny, metodyczny i koncepcyjny. Częściowym rozwiązaniem tego problemu stało się
1
Department of Cartography, faculty of Geodesy and Cartography, Warsaw University of Technology
58
ROBERT OLSZEWSKI
przyjęcie i sukcesywne wdrażanie zapisów unijnej dyrektywy INSPIRE i polskiej ustawy o infrastrukturze informacji
przestrzennej.
Akty prawne wysokiej rangi określają jednak tylko ogólne zasady tworzenia infrastruktury geoinformacyjnej. Do
budowy nowoczesnych i funkcjonalnych baz danych przestrzennych o charakterze referencyjnym i tematycznym niezbędne
jest bowiem szczegółowe określenie modelu koncepcyjnego poszczególnych baz, sposobu ich zasilania, wykorzystania
oraz przetwarzania zgromadzonych w nich danych. Najistotniejszym elementem tego procesu nie jest zatem działanie
legislacyjne, lecz właściwe zrozumienie otaczającej nas rzeczywistości geograficznej, przekładające się na utworzenie
poprawnego modelu kartograficznego realizowanego w postaci bazy danych przestrzennych. Po okresie gwałtownego rozwoju technologicznego i fascynacji nowoczesnymi rozwiązaniami informacyjnymi, niezbędna jest zatem głęboka refleksja
metodyczna i koncepcyjna poprzedzająca dalsze działania wdrożeniowe.
1. introduction
When in the 1960s the term “global village” was
used for the first time to describe cross-border economic,
demographic and political processes it was hard to believe
that half a century later, in the era of the ubiquitous Internet, this metaphor is no longer merely a means of literary
expression and has become a true illustration of globalization (McLuhan, 1962). One of the essential elements
of a global process of informatization is to build regional
and intercontinental geoinformation infrastructures. One
component of this process is the creation of spatial databases and visualization of their data. Thus modelling
of geographic information in a supraregional scale has
become a subject of not only cartographic but also legal,
social and information technology works. In this context,
Prof. Michael Wood’s message “The 21st century world
- no future without cartography” (2001), delivered at a
conference of the International Cartographic Association
in Beijing is particularly important. former President of
ICA notes that although the name itself was a relatively
recent discipline, cartography is an expression of one of
the oldest impulses shaping the humanity - efforts to map
the surrounding world. Wood argues that the traditional
“cartographic dichotomy” - the classic division between
creators and users of cartographic work - is now being
replaced by ‘linguistic analogy’ denoting the full use of
the language of cartography by the general public. Just as
knowledge of a language does not only allow us to read
existing studies but also to write them, so a basic knowledge of cartographic methods not only allows the use of
maps, but also their co-creation and sharing for instance
in the form of websites. It should be noted that in the process of universal “mapping of the world” understood in
this way, the role of professional cartographers would be
not so much to create the resulting map compositions but
rather widespread education on methods of presentation
and the correct modelling of the reference information in
spatial databases, which are canvas for thematic and trade
studies.
2. cartographic modelling
Modelling and imaging of the surrounding geographic area has a tradition much older than the formal
cartographic techniques (Peters, 1978). Dated at tens of
thousands years old totemic paintings on the walls of
the cave of Lascaux (french Aquitaine), a product of
Palaeolithic art, indicate the significance of spatial relationships in learning and exploration of the world. The
development of forms of human communication through
shared learning of space was for our ancestors not so
much religious art or applied art as just a prosaic visual
art of survival. According to Peters (1978) cognitive
maps can be an important factor in the intellectual evolution of hominids. Throughout human history, our external conditions of life have undergone significant change,
however, what has not changed is the way the mind
works, the way we become involved in our interpretations of reality, how we identify ourselves with limited
aspects of ourselves, and how our commitment and fears
determine our actions. It can therefore be concluded that
the development of the ability of the mapping of the sur-
GEOINfORMATICA POLONICA
11: 2012
ZBIGNIEW KASINA1
tHe AnALYSiS oF tHe eFFectiVeneSS oF SiMULtAneoUS inVerSion
oF tUrninG AnD HeAD WAVeS FirSt BreAKS – MoDeL StUDY2
Key words:
geophysics, seismic methods, refraction tomography, traveltime tomography
Abstract
In the presented paper the model data were used to analyse the effectiveness of simultaneous inversion of the turning
and head waves first breaks in comparison with the effectiveness of the inversion of only first breaks of turning waves or
head waves. The analysis was undertaken for the gradient velocity models of the near surface layer with the low velocity
anomaly and for the CDP aquisition. The effect of the numerical ray tracing on the traveltime calculations and inversion
results was estimated taking into account the wave equation modeling of seismic records. The effect of the errors of the
starting velocity field in the process of inversion as well as the effect of spatial smothing of resulting velocity fields were
considered too. The analysis confirmed some improvement in the imaging of the near surface velocity anomalies when we
use simultaneous inversion of the turning and head waves first breaks.
ANALIZA EfEKTYWNOŚCI JEDNOCZESNEJ INWERSJI PIERWSZYCH WSTĄPIEń fALI REfRAGOWANEJ
I CZOŁOWEJ – STUDIUM MODELOWE
Słowa kluczowe
geofizyka, metody sejsmiczne, tomografia refrakcyjna, tomografia czasów przebiegu
Abstrakt
W przedstawionej pracy wykorzystano dane modelowe do analizy efektywności jednoczesnej inwersji pierwszych
wstąpień fal czołowych i refragowanych w porównaniu do efektywności inwersji tylko pierwszych wstąpień fali refragowanej
lub czołowej. Analizę podjęto dla gradientowych modeli strefy przypowierzchniowej z niskoprędkościową anomalią dla
University of Science and Technology AGH, faculty of Geology, Geophysics & Environment Protection, Department of Geophysics,
Cracow, Poland
2
The paper was prepared within the project of MNiSW no. N N525 168735 realized in the period 2008 - 2011 in the Department of
Geophysics, contract AGH no. 11.11.140.769
1
68
ZBIGNIEW KASINA
akwizycji metody pokryć wielokrotnych. Oszacowano wpływ numerycznego trasowania promieni na wyniki obliczeń
czasów przebiegu i inwersji uwzględniając wyniki modelowania rekordów sejsmicznych z równania falowego. Rozważano
także wpływ błędów startowego pola prędkości w procesie inwersji, jak również wpływ przestrzennego wygładzania
wynikowych pól prędkości. Analiza potwierdziła pewną poprawę w odwzorowaniu anomalii prędkościowych strefy przypowierzchniowej, gdy wykorzystujemy jednoczesną inwersję pierwszych wstąpień fal czołowych i refragowanych.
introduction
Defining the velocity fields in the near surface layer
is an essential stage of seismic data processing. Its results
determine the accuracy of the field static corrections calculations and the good quality of resulting seismic sections. The correct imaging of velocity fields in the near
surface layer is very also important when we construct the
shallow velocity part of migration velocity model.
The problem of the static corrections estimation
comes into special prominence in the commonly used
vibrator method of land seismic acquisition when often
the only source of the information about low velocity
layer are the traveltimes of first breaks on seismic records.
Three approaches are used in this case. In the first approach the times of first breaks are treated as the arrival
times of head waves connected with the succeding refractors of low velocity layer. These traveltimes (head waves
hodographes) are interpreted using refraction, well known
methods yielding an approximate layered velocity model
of the near surface medium. To improve the results of refraction interpretation we can apply the generalized linear
inversion (GLI) using the well known Hampson-Russell
program (Hampson, Russell 1984). The second approach
treats the traveltimes of the first breaks as the arrival times
of turning waves propagating in the gradient medium of
low velocity layer. The velocity fields are estimated by
means of tomographic inversion in this case (Zhu et al.
1992, Stefani 1995, Lanz et al. 1998, Zhu 2002). In the
third approach we use in the process of inversion the first
breaks of head waves generated by the refractor in the
bottom of low velocity layer.
Each of the above described approaches has its own
limitations. In the first case we can estimate only layered
model with constant velocites in each layer. It is difficult
to recover the local velocity heterogeneities in the indi-
vidual layers. In the second case the tomographic inversion of the traveltimes of turning wave with dominating
ray trajectories deviated from vertical and horizonal directions yields in many cases the relative weaker horizontal
resolution. In the third case the tomographic inversion of
the traveltimes of head waves with dominating vertical
ray trajectories characterizes of weak vertical resolution
manifesting in smearing velocity anomalies in vertical
direction toward surface.
In the case of the gradient medium with local velocity anomalies placed above the strong refractor none of
the described solutions create the possiblity of the optimal estimation of the velocity fields. The solution may
be the simultaneous inversion of the turning wave first
breaks connected with gradient low velocity layer and
head wave first breaks connected with the strong refractor
in the bottom of near surface layer. The analysis of the
effectiveness of such a approach based on the model data
was undertaken in the presented paper.
1. construction of the seismogeological models of low
velocity models and the generation of theoretical traveltimes of the turning and head waves
for the purpose of the model calculations realized
for the case of turning waves, the gradient models (with
positive vertical velocity gradient) without anomalies and
with low velocity shallow anomaly were constructed. for
the purpose of the model calculations realized for the case
of head waves the refractor was placed in the bottom of
the gradient medium. The gradient model is presented in
fig. 1. The velocity anomaly had the dimensions: width
300 m, height 20 m. The depth of the top of anomaly was
10 m and the velocity inside anomaly was 600 m/s. The
velocity outside the anomaly was increasing from the